Saturated or unsaturated, respectively, polycyclic hydrocarbons consisting of fused five-membered rings, commonly but not necessarily incorporating the skeleton of quinacene (tricyclo[5.2.1.0
4,10]deca-2,5,8-triene): E.g.
P04751.png
bicyclo[3.3.0]octane, dodecahedrane.
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1360 (https://doi.org/10.1351/pac199567081307)